CN104795891A - Intelligent main transformer online monitoring system in distribution line - Google Patents

Abstract

An intelligent on-line monitoring system for a main transformer in a power distribution line, the system includes a sensor signal acquisition system connected with various sensors, the sensors at least include a vibration sensor and a temperature sensor installed on the outer box of the main transformer, placed on The pressure sensor of the oil tank of the main transformer, the sound sensor placed near the main transformer; the sensor signal acquisition system is composed of a main controller composed of a microprocessor and peripheral circuits, and the main controller collects various signals collected by each sensor It becomes the transmission data and uploads it to the A8 host computer that can be monitored in real time; the system also includes a harmonic meter that connects to three voltages and samples voltage signals. The harmonic meter has a wireless communication module and an A8 upper computer. It has the characteristics of reasonable structure, convenient, reliable and safe use, real-time monitoring and sensitive monitoring, and the realization of safe operation of power distribution lines.

Description

An intelligent online monitoring system for main transformers in power distribution lines

technical field

The invention relates to an intelligent online monitoring system for main transformers in power distribution lines, belonging to the technical field of safety monitoring of power distribution equipment.

Background technique

The safe operation of power distribution lines is the basis for ensuring the safe use of electricity in all walks of life, and the safe operation of power distribution lines depends on the normal operation of power distribution equipment. Due to long-term overload operation of power distribution equipment, such as transformers, once a fault occurs, it is Affect the safe operation of power distribution lines. For this reason, online monitoring of power distribution equipment, especially the main transformer, will help the power sector to understand the operation of the main transformer in a timely manner, and provide reliable information for reducing the accident rate and reducing the repair time of accidents. protection.

Contents of the invention

The purpose of the present invention is to overcome the deficiencies of the existing technology, and provide a reasonable structure composition, convenient, reliable, safe, real-time monitoring and sensitive monitoring, and realize the intelligent online monitoring of the main transformer in the distribution line for safe operation of the distribution line. system.

The object of the present invention is achieved through the following technical solutions. An intelligent on-line monitoring system for main transformers in power distribution lines. The system includes a sensor signal acquisition system connected with various sensors. The sensors at least include Vibration sensors and temperature sensors on the outer box of the transformer, pressure sensors placed on the oil tank of the main transformer, and sound sensors near the main transformer; the sensor signal acquisition system is composed of a main controller formed by a microprocessor and a peripheral circuit. The main controller converts various signals collected by various sensors into transmission data, and uploads them to the A8 host computer for real-time monitoring; the system also includes a harmonic meter that connects to three voltages and samples the voltage signals. , the harmonic meter has a wireless communication module and the A8 host computer for wireless transmission of voltage data.

The vibration sensor of the present invention is a CZ891 vibration sensor that can directly convert a vibration signal with a measuring range of 0-10mm/s into a 4-20mA output current signal, and the sensor signal acquisition system converts the vibration current signal through AD sampling. transmit data for vibration;

The temperature sensor is at least one DS18B20 digital temperature sensor that can directly convert the collected temperature signal into a digital signal through AD conversion, and the sensor signal acquisition system directly reads the digital signal of the temperature through an I/O interface and It becomes the transmitted data of temperature;

The pressure sensor is a 20B-10MPIG pressure sensor that can directly convert a pressure signal with a range of 0-10Mpa into a 4-20mA output current signal. The sensor signal acquisition system converts the pressure current signal into a pressure signal through AD sampling. transmit data;

The sound sensor is a WST60M noise sensor that can directly convert the sound signal into a noise digital signal through AD, and the sensor signal acquisition system communicates with the WST60M noise sensor through a serial interface and reads the noise digital signal and transmit data that turns it into noise;

The sensor signal acquisition system uses STM32F103 microprocessor as the main controller, and the main controller is connected to the A8 host computer that can upload and receive various transmission data through a serial interface.

The harmonic meter mainly includes an STM32 processor as the core, the STM32 processor is respectively provided with a voltage input terminal and a current input terminal through the ATT7022 metering chip, and the STM32F103 microprocessor is respectively connected with a wireless communication module, Keyboard display module-MODBUS communication module.

The sensor signal acquisition system of the present invention is also connected with at least one pyro-infrared sensor installed near the main transformer, which can sense the movement of small animals to control the change of high and low levels. The sensor signal acquisition system collects the pyro-infrared sensor generated The high and low level signal, and through the change of the high and low level signal, the small animal monitoring transmission data is uploaded and received by the A8 host computer;

The temperature sensor has two paths, one of which is installed close to the outer box of the main transformer to collect the temperature of the outer box of the main transformer; the other is installed on the wall bushing of the main transformer to collect the temperature of the terminal box;

The harmonic meter is installed in a switch cabinet.

What the A8 upper computer of the present invention selects is a kind of AM335X microprocessor based on ARMcortex-A8, has the SD card greater than 2G, and it connects the liquid crystal display that can show various data in real time by parallel data interface, through two The serial port is connected with the GPRS module and the RF module respectively, and sends a short message to the corresponding terminal with a SIM card through the at least one GPRS module; the A8 host computer and the sensor signal acquisition system are all installed in a monitoring In the box, the liquid crystal display is arranged on the front of the monitoring box.

The present invention mainly aims at the deficiencies in traditional transformer fault diagnosis, especially the problem of difficult diagnosis of non-thermal faults and thermal faults with inconspicuous early heating, and uses the vibration signal of the transformer itself to judge whether there is a potential fault in the transformer; By installing multiple sets of sensors on the transformer oil tank, the vibration acceleration signals and ambient noise signals of the top, bottom, front, and side of the transformer oil tank can be sampled, and the temperature of the transformer and the harmonic content of the voltage output by the transformer can be monitored at the same time. Real-time online monitoring of internal faults such as winding deformation, looseness, and iron core looseness.

The invention is simple in installation and sensitive in monitoring. Once the transformer is abnormal, the GPRS module in the device will send information such as transformer alarm status, fault type and fault time to the set background system (or mobile phone) in time, so that maintenance personnel can find out and eliminate it in time. Transformer failure hidden danger, improve the power supply quality of the grid.

The invention has the characteristics of reasonable structure and composition, convenient, reliable and safe use, real-time monitoring and sensitive monitoring, and the realization of safe operation of power distribution lines.

Description of drawings

Fig. 1 is a schematic diagram of the structural composition of the present invention.

Fig. 2 is a functional block diagram of the sensor signal acquisition system of the present invention.

Fig. 3 is a functional block diagram of the harmonic meter of the present invention.

Fig. 4 is a functional block diagram of the A8 upper computer of the present invention.

detailed description

The present invention will be described in detail below in conjunction with the accompanying drawings: As shown in Figures 1 and 2, a main transformer intelligent online monitoring system in a distribution line according to the present invention, the system includes a sensor signal acquisition system connected with multiple sensors System 1, the sensor includes at least a vibration sensor 3 and a temperature sensor 4 installed on the outer box of the main transformer 2, a pressure sensor 5 placed in the oil tank of the main transformer, and a sound sensor 6 placed near the main transformer; the sensor The signal acquisition system 1 is composed of a main controller composed of a microprocessor and peripheral circuits. The main controller becomes transmission data by collecting various signals collected by each sensor, and uploads it to the A8 upper computer 7 for real-time monitoring; The system also includes a harmonic meter 8 that is connected to three voltages and samples voltage signals. The harmonic meter 8 has a wireless communication module 9 and an A8 host computer 7 for wireless transmission of voltage data.

As shown in the figure, the vibration sensor 3 of the present invention is a CZ891 vibration sensor that can directly convert a vibration signal with a range of 0-10mm/s into a 4-20mA output current signal, and the sensor signal acquisition system 1 is passed through AD Sampling turns the vibrating current signal into vibrating transmission data;

The temperature sensor 4 is at least one DS18B20 digital temperature sensor that can directly convert the collected temperature signal into a digital signal through AD conversion, and the sensor signal acquisition system 1 directly reads the digital signal of the temperature through an I/O interface And turn it into the transmission data of temperature;

The pressure sensor 5 is a 20B-10MPIG pressure sensor that can directly convert the pressure signal with a range of 0-10Mpa into a 4-20mA output current signal, and the sensor signal acquisition system 1 converts the pressure current signal into Pressure transmission data;

The sound sensor 6 is a WST60M noise sensor that can directly convert the sound signal into a noise digital signal through AD, and the sensor signal acquisition system 1 communicates with the WST60M noise sensor through a serial interface and reads the noise digital signal. signal and turn it into noise for transmitted data;

The sensor signal acquisition system 1 selects STM32F103 microprocessor as the main controller, and the main controller is connected to an A8 host computer that can upload and receive various transmission data through a serial interface.

As shown in Fig. 3, described harmonic meter 8 mainly comprises a STM32 microprocessor 10 as core, and this STM32 microprocessor 10 is respectively provided with voltage input terminal 12 and current input terminal 13 by ATT7022 metering chip 11, and described The STM32F103 microprocessor 10 is respectively connected with a wireless communication module 9 , a keyboard display module 14 and a MODBUS communication module 15 .

In Fig. 3, the voltage and current input terminals 12 and 13 carry out three-way voltage input and three-way current input, and enter the metering chip 11 after the voltage is divided, and the metering chip 11 can calculate values such as electric quantity and electric energy, and send the data to the STM32 microprocessing In the device 10, the STM32 microprocessor processing core calculates the voltage, current, power, electric energy, etc., as well as the harmonic content value, and displays the value. The wireless communication module 9 is used for wireless communication, and the remote end can inquire about the relevant power or electric energy value through wireless communication according to a certain protocol.

The sensor signal acquisition system 1 is also connected with at least one pyro-infrared sensor 16 installed near the main transformer 2, which can sense the movement of small animals to control the change of high and low levels. The sensor signal acquisition system 1 collects pyro-infrared sensors. The high and low level signals generated by the sensor 16, and through the change of the high and low level signals constitute the A8 host computer 7 for uploading and receiving small animal monitoring transmission data;

The temperature sensor 4 has two paths, wherein one temperature sensor 4 is arranged close to the outer box of the main transformer 2 to collect the temperature of the outer box of the main transformer 2; the other is installed on the wall bushing of the main transformer 2 to collect The temperature of the terminal box;

The harmonic meter 8 is installed in a switch cabinet 17 .

As shown in Fig. 4, what described A8 host computer 8 selects is a kind of AM335X microprocessor based on ARMcortex-A8, has the SD card 18 greater than 2G, and it connects the liquid crystal that can display various data in real time by parallel data interface Display 23 is respectively connected with GPRS module 20 and RF module 21 by two serial ports 19, and sends short message to corresponding terminal machine with SIM card by described at least one GPRS module 20; Described A8 upper computer 8 and the sensor signal acquisition system 1 are installed in a monitoring box 22 , and the liquid crystal display 23 is arranged on the front of the monitoring box 22 .

Embodiment: shown in Fig. 1-3, the sensor signal collection system of the present invention mainly takes STM32F103 microprocessor as core, and its main frequency is up to 72MHZ, collects the data of vibration, pressure, infrared, temperature, noise sensor in real time, and Upload to the A8 host computer system. The superior performance and rich system resources of STM32 ensure the fast and efficient operation of the entire system, the expansion of various functions and real-time monitoring.

The main function:

1. One-way mechanical vibration monitoring (the vibration sensor is installed on the outer box of the main transformer). Through the CZ891 vibration sensor, the vibration signal with a range of 0-10mm/s is directly converted into a 4-20mA output current signal. The sensor signal acquisition system STM32F103 collects the data through AD sampling and uploads it to the A8 system for real-time monitoring.

2. One way to monitor the temperature of the outer box (0-100 degrees, using a temperature sensor). The DS18B20 digital temperature sensor converts the temperature signal directly into a digital signal through AD conversion. The sensor signal acquisition system STM32F103 only needs to read the temperature information of the outer box through one I/O port and upload it to the A8 system for real-time monitoring.

3. One-way terminal box temperature monitoring (0-100 degrees, using temperature sensor). The DS18B20 digital temperature sensor converts the temperature signal directly into a digital signal through AD conversion. The sensor signal acquisition system STM32F103 only needs to read the temperature information of the box through one I/O port and upload it to the A8 system for real-time monitoring.

4. All the way through the wall bushing temperature detection (0-100 degrees, heat expansion of the wire causes damage to the insulation layer). The DS18B20 digital temperature sensor converts the temperature signal directly into a digital signal through AD conversion. The sensor signal acquisition system STM32F103 only needs to read the temperature information of the wall bushing through one I/O port and upload it to the A8 system for real-time monitoring.

5. Noise monitoring along the way (using sound sensor). The noise signal is converted into a digital signal by AD through the WST60M noise sensor. The sensor signal acquisition system STM32F103 communicates with the WST60M noise sensor through a serial port, reads the noise data, and uploads it to the A8 system for real-time monitoring.

6. One-way fuel tank pressure monitoring (transformer manufacturer is required to provide the installation location of the pressure sensor). The 20B-10MPIG pressure sensor directly converts the pressure signal with a range of 0-10MPa into a 4-20mA output current signal. The sensor signal acquisition system STM32F103 collects the data through AD sampling and uploads it to the A8 system for real-time monitoring.

7. Monitoring of small animals near the main transformer along the way (using pyro-infrared sensors for monitoring). The infrared sensor BK-P02C senses the movement of small animals to control the change of high and low levels. The sensor signal acquisition system STM32F103 judges whether there are small animals by collecting the changes of high and low levels, and uploads the information to the A8 system.

In addition, the sensor acquisition system also reserves 3-way temperature monitoring and 3-way infrared monitoring functions.

A8 system function:

a. When the above monitoring is abnormal (exceeding the set value), send a text message to the power company through GPRS (using SIM card);

b. The above monitoring data can be stored in the SD card, and the staff can unplug the SD card and import the data into the computer for analysis;

c. FIRD inspection two-way identification.

Harmonic meter function: 31st harmonic monitoring of three-phase voltage (using existing digital multifunctional harmonic meter technology). Monitor the harmonic content of the transformer output through the harmonic meter.

The harmonic meter described is a PD6804Z-9SYD installed digital network electrical measuring instrument, which is a 32-bit high-performance processing chip based on STM32, a special metering chip, and a wireless communication module, which can achieve high precision and real-time measurement of all commonly used Power parameters: three-phase voltage, three-phase current, active power, reactive power, frequency, power factor, active energy, reactive energy, four-quadrant energy, etc.

Claims (5)

1. A main transformer intelligent online monitoring system in a power distribution line, the system includes a sensor signal acquisition system connected with multiple sensors, characterized in that: the sensors at least include a vibration sensor installed on the main transformer outer box , a temperature sensor, a pressure sensor placed in the oil tank of the main transformer, and a sound sensor placed near the main transformer; the sensor signal acquisition system is composed of a main controller composed of a microprocessor and a peripheral circuit. The various signals collected by the sensor are transformed into transmission data, which are uploaded to the A8 host computer for real-time monitoring; the system also includes a harmonic table that connects three voltages and samples the voltage signal, and the harmonic table has The wireless communication module performs wireless transmission of voltage data with the A8 host computer. 2. The main transformer intelligent online monitoring system in the power distribution line according to claim 1, characterized in that: The vibration sensor is a CZ891 vibration sensor that can directly convert the vibration signal with a range of 0-10mm/s into a 4-20mA output current signal, and the sensor signal acquisition system converts the vibration current signal into vibration through AD sampling the transmission data; The temperature sensor is at least one DS18B20 digital temperature sensor that can directly convert the collected temperature signal into a digital signal through AD conversion, and the sensor signal acquisition system directly reads the digital signal of the temperature through an I/O interface and It becomes the transmitted data of temperature; The pressure sensor is a 20B-10MPIG pressure sensor that can directly convert a pressure signal with a range of 0-10Mpa into a 4-20mA output current signal. The sensor signal acquisition system converts the pressure current signal into a pressure signal through AD sampling. transmit data; The sound sensor is a WST60M noise sensor that can directly convert the sound signal into a noise digital signal through AD, and the sensor signal acquisition system communicates with the WST60M noise sensor through a serial interface and reads the noise digital signal and transmit data that turns it into noise; The sensor signal acquisition system uses STM32F103 microprocessor as the main controller, and the main controller is connected to the A8 host computer that can upload and receive various transmission data through a serial interface. 3. The harmonic meter mainly includes an STM32 processor as the core, the STM32 processor is respectively provided with a voltage input terminal and a current input terminal through the ATT7022 metering chip, and the STM32F103 microprocessor is respectively connected with a wireless communication Module, keyboard display module-MODBUS communication module. 4. The intelligent on-line monitoring system for the main transformer in the power distribution line according to claim 2, characterized in that: the sensor signal acquisition system is also connected with at least one installed near the main transformer, which can sense the movement of small animals to control A pyroelectric infrared sensor with high and low level changes, the sensor signal acquisition system collects the high and low level signals generated by the pyroelectric infrared sensor, and through the change of the high and low level signals constitutes an A8 host computer for uploading and receiving small animal monitoring transmission data; The temperature sensor has two paths, one of which is installed close to the outer box of the main transformer to collect the temperature of the outer box of the main transformer; the other is installed on the wall bushing of the main transformer to collect the temperature of the terminal box; The harmonic meter is installed in a switch cabinet. 5. According to claim 1 or 2, 3 described main transformer intelligent online monitoring system in power distribution line, it is characterized in that: what described A8 host computer selects is a kind of AM335X microprocessor based on ARMcortex-A8, with There is an SD card greater than 2G, which is connected to a liquid crystal display that can display various data in real time through a parallel data interface, and is connected to a GPRS module and an RF module through two serial ports, and sends a short message to Correspondingly, a terminal with a SIM card; the A8 host computer and the sensor signal acquisition system are all installed in a monitoring box, and the liquid crystal display is arranged on the front of the monitoring box.